Many a bodybuilder, crossfitter and average gym goer alike have signed up to the gospel of creatine. But what is it, and is it worth the hype?
What is it?
Creatine is a small peptide, which is basically like a very very small protein. It is made from three amino acids – L-arginine, glycine and methionine. It is found predominantly in skeletal muscle, and also to a lesser degree in the brain (see review by Kreider et al 2017).
What does it do?
Muscular energy!! It supports high power explosive movement and strength. Creatine powers one of the pathways by which energy is produced in cells (the phosphagen pathway), and it is the pathway initially recruited when we suddenly ramp up our movement levels – for example in an explosive jump or heavy lift. Perhaps unsurprisingly, it is found in the highest concentrations in the fast-twitch (Type II) muscle fibres, i.e. those that are recruited for high energy explosive and strength movement.
Creatine is a short-term energy source as there is an upper limit on the amount of creatine a muscle cell can hold. It is thought that on average the creatine pathway can support ~10 secs of max effort activity. Hence it is the main energy provider in a high power short blast of movement, but not in a marathon!
For those of you who are scientifically inclined – creatine forms a high-energy phosphate store (phosphocreatine) in cells. To generate energy (ATP), phosphocreatine donates its phosphate to ADP to form ATP + creatine, thus providing the cell with the energy (ATP) for muscle contraction (Ellington, WR 2001). It is an anaerobic pathway (does not require oxygen), just like the more commonly known glycolytic pathway that produces the lactic acid we all know about when our muscles burn in pain as we train!
There is also evidence that creatine has broader health benefits relating to injury prevention and recovery, neurological health, and heat stress. Whether these are related to creatine’s role in energy production, or other mechanisms, it remains to be definitively determined (see review by Kreider et al 2017).
How do we get it?
Most of the creatine in our body we make ourselves, in our livers. Creatine is also present in animal protein sources in the diet, i.e. meat, fish and eggs, however it is broken down in the cooking process and so the diet tends not to be a major source for most people.
Should I supplement with it?
If you train at high intensity or for explosive power and strength – yes!
Although there is a limit to the amount of creatine a cell can hold, it seems that naturally we are never at full capacity, even if we do train regularly (which makes the creatine pathway stronger and more adept at producing energy) (see review by Kreider et al 2017). By supplementing with creatine, it has been shown that you increase the amount of creatine and phosphocreatine in muscle cells, and the energy you can produce by this pathway (see review by Kreider et al 2017). In essence – creatine is a proven ergogenic aid (enhances athletic performance).
In addition, creatine draws water into muscle cells that it enters. This means you get an initial swelling and increase in weight of muscle cells when you take creatine. Swelling through water uptake is known to stimulate cell growth through blocking protein degradation and stimulating DNA synthesis. Creatine does appear to have a longer term effect on actual muscle mass (i.e. not just as a result of water weight!). This may be in part a result of the impact of swelling on cell growth, as well as the more explosive and stronger muscle movement enabled by the higher creatine levels and the impact this has on muscle hypertrophy, and also potentially through direct activation of the pathways that activate muscle protein synthesis (see review by Farshidfar et al 2017).
Some have suggested that creatine supplementation causes kidney damage, but multiple studies have failed to provide evidence this is the case (Gualano et al 2010, as an example).
Okay, so what, how much and when?
Creatine monohydrate is the cheapest form, and there is no evidence that any other form is any better (see review by Kreider et al 2017)!
When you first start taking creatine, it is recommended to begin with a 5-7 day loading phase, where you take 0.3g/kg bodyweight daily. Thereafter, it is recommended to take a dose of 0.03-0.06g/kg daily (see review by Kreider et al 2017). Some have said you should cycle creatine supplementation (i.e. have periods of taking it and periods of not taking it), but there is no evidence this provides any benefit. Although it is stored in the body, it does degrade over time and so to maintain levels you want to be keeping your levels continually topped up.
In terms of when to take it, there is no strong evidence to say it is most effective if taken before, during or after training. Given that it takes time to travel through the digestive system and into cells, taking it immediately before or during a workout is going to have little benefit on that particular training session. So, take at a time that is most convenient for you.
To note –
1. Creatine should be taken with a lot of water, to avoid stomach cramps. Some people suffer nausea or diarrhoea from taking it as a supplement – if this happens, try taking it in smaller doses spread through the day, and alongside food.
2. Expect weight gain in the initial loading phase in particular – as explained above, water is drawn into the muscle along with the creatine. The more muscle you have to start with, the greater the potential creatine and water uptake and the more weight you can expect to gain – potentially up to 1-1.5kg.
Anything else to consider?
Some studies have looked at the effect of combining caffeine and creatine on performance, as caffeine is also a known ergogenic aid. It certainly seems that when taken together performance in HIIT and sprint activities are increased (Doherty et al 2002, Lee et al 2011). There is some evidence, however, that caffeine can blunt the effect of creatine on muscle power output if they are both taken together (Vandenberghe et al 1996). As such, you should continue taking creatine steadily over time (as recommended above), and then caffeine immediately before training.
Doherty M, Doherty M1, Smith PM, Davison RC, Hughes MG. Caffeine is ergogenic after supplementation of oral creatine monohydrate. Med Sci Sports Exerc. 34(11):1785-92, 2002.
Ellington, WR. Evolution and physiological roles of phosphagen systems. Annual Rev Physiol. 63 (1): 289–325, 2001.
Farshidfar F, Pinder MA, Myrie SB. Creatine Supplementation and Skeletal Muscle Metabolism for Building Muscle Mass- Review of the Potential Mechanisms of Action. Curr Protein Pept Sci. 18(12):1273-1287, 2017
Gualano B, Ferreira DC, Sapienza MT, Seguro AC, Lancha AH Jr. Effect of short-term high-dose creatine supplementation on measured GFR in a young man with a single kidney . Am J Kidney Dis. 55(3):e7-9, 2010.
Kreider RB, Kalman DS, Antonio J, Ziegenfuss TN, Wildman R, Collins R, Candow DG, Kleiner SM, Almada AL, Lopez HL. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 13;14:18, 2017.
Lee CL, Lin JC, Cheng CF. Effect of caffeine ingestion after creatine supplementation on intermittent high-intensity sprint performance. Eur J Appl Physiol. 111(8):1669-77, 2011.